Subtract 7/10 from 28/81
28/81 - 7/10 is -287/810.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 10 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 81 × 10 = 810,
28/81 = 28 × 10/81 × 10 = 280/810 - Likewise, for the 2nd fraction, since 10 × 81 = 810,
7/10 = 7 × 81/10 × 81 = 567/810 - Subtract the two like fractions:
280/810 - 567/810 = 280 - 567/810 = -287/810
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